Question
If a tank can be filled by a tap in 12 hours, but due to
an outlet, it actually takes 9 hours longer to fill the tank, find the duration in which the outlet alone would empty the tank?Solution
Let tap ‘A’ fill the tank and tap ‘B’ empty the tank. Taking LCM of 12 and 21 = 84 Efficiency of A = 7 Efficiency of (A – B) = 4 Efficiency of B = 7 – 4 = 3 Tap B will empty the tank = 84/3 = 28 So, tap B will empty the tank in 28 hours.
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